BACKGROUND AND OBJECTIVES: Awake minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) generates minimal surrounding tissue damage and has been shown to be a safe, time-effective, and cost-reductive technique in single-level procedures. The purpose of this study was to advocate for the utilization of multilevel MIS-TLIF even in challenging cases as it has demonstrated positive outcomes. METHODS: Chart review was conducted for consecutive patients undergoing awake multilevel MIS-TLIF from 2020 to 2023. Various demographic, preoperative, and postoperative variables were collected and descriptively analyzed. RESULTS: Sixteen patients underwent multilevel awake MIS-TLIF at our institution during the specified period. Among them, 87.5% underwent a two-level procedure and 12.5% a three-level procedure. The median age ± IQR was 69.5 ± 11 years, with a slight male predominance (56.25%). Common comorbidities included hypertension (56.25%), obesity (37.5%), sleep apnea (25%), and type 2 diabetes (18.75%). The American Society of Anesthesiologists risk was 2 in 43.75% of patients and 3 in 56.25%. All patients presented pain, and 12.5% showed motor deficit. Intraoperative data showed a median of 196 minutes in the operating room where 156 ± 27.75 minutes corresponded to actual procedure time. The median estimated blood loss was 50 ± 70 cc. In the immediate postoperative period, 1 patient had nausea and emesis, and 1 reported fatigue. The median pain score during this period was 4.6 ± 2.03. Pain control medications were required for various patients, with methocarbamol (50%), hydromorphone (37.5%), and oxycodone (25%) being the most commonly prescribed in the postanesthesia care unit. No patient had new neurological deficits after the surgical intervention. The median length of stay was 2 days ±1.25. All patients were discharged with no complications. CONCLUSION: Multilevel awake MIS-TLIF emerges as a safe and effective technique for complex cases, enhancing patient quality of life with minimal blood loss and postoperative pain.
Minimally invasive posterior cervical foraminotomy versus the anterior transcorporeal approach for cervical radiculopathy: a systematic review and meta-analysis
OBJECTIVE Surgical decompression is often indicated for symptomatic cases of cervical radiculopathy. In the cervical spine, minimally invasive posterior cervical foraminotomy (MIS-PCF) and the anterior transcorporeal approach (ATCA) are modern techniques available to surgeons. This systematic review and single-arm meta-analysis aimed to assess surgical and patient-reported outcomes of MIS-PCF and ATCA for cervical radiculopathy. METHODS A systematic review of the literature was conducted using 1) Ovid; 2) Epub Ahead of Print and In-Process, In-Data-Review & Other Non-Indexed Citations; and 3) Scopus databases, which reported outcomes following cervical decompression using MIS-PCF or the ATCA. Specifically, baseline characteristics, operative outcomes, and changes in visual analog scale (VAS) neck pain score were assessed. The quality of the studies was graded using the modified Newcastle-Ottawa Scale for observational studies. RESULTS Forty studies with 1661 patients were identified. The comparative analysis of both techniques revealed no significant differences in complication (7%, 95% CI 5%–10%, p = 0.75) or reoperation rates (5%, 95% CI 3%–7%, p = 0.41). Additionally, there were no significant differences in estimated blood loss (55.39, 95% CI 44.62–66.16 ml, p = 0.55) or operative time (85.15, 95% CI 65.38–104.92 minutes, p = 0.05). The ATCA showed significantly greater improvement (p < 0.01) in VAS neck pain scores following surgery (ATCA point reduction 6.7, 95% CI 6.0–7.5 points vs MIS-PCF 3.0, 95% CI 1.0–5.0 points). CONCLUSIONS The ATCA and MIS-PCF are effective modern techniques for the surgical treatment of radiculopathy. Both approaches showed comparable postoperative outcomes, including complication and reoperation rates. However, the ATCA was shown to provide significantly greater improvement in VAS neck pain scores.
Proton versus photon adjuvant radiotherapy: a multicenter comparative evaluation of recurrence following spinal chordoma resection
OBJECTIVE Chordomas are rare tumors of the skull base and spine believed to arise from the vestiges of the embryonic notochord. These tumors are locally aggressive and frequently recur following resection and adjuvant radiotherapy. Proton therapy has been introduced as a tissue-sparing option because of the higher level of precision that proton-beam techniques offer compared with traditional photon radiotherapy. This study aimed to compare recurrence in patients with chordomas receiving proton versus photon radiotherapy following resection by applying tree-based machine learning models. METHODS The clinical records of all patients treated with resection followed by adjuvant proton or photon radiotherapy for chordoma at Mayo Clinic were reviewed. Patient demographics, type of surgery and radiotherapy, tumor recurrence, and other variables were extracted. Decision tree classifiers were trained and tested to predict long-term recurrence based on unseen data using an 80/20 split. RESULTS Fifty-three patients with a mean ± SD age of 55.2 ± 13.4 years receiving surgery and adjuvant proton or photon therapy to treat chordoma were identified; most patients were male. Gross-total resection was achieved in 54.7% of cases. Proton therapy was the most common adjuvant radiotherapy (84.9%), followed by conventional or external-beam radiation therapy (9.4%) and stereotactic radiosurgery (5.7%). Patients receiving proton therapy exhibited a 40% likelihood of having recurrence, significantly lower than the 88% likelihood observed in those treated with nonproton therapy. This was confirmed on logistic regression analysis adjusted for extent of tumor resection and tumor location, which revealed that proton adjuvant radiotherapy was associated with a decreased risk of recurrence (OR 0.1, 95% CI 0.01–0.71; p = 0.047) compared with photon therapy. The decision tree algorithm predicted recurrence with an accuracy of 90% (95% CI 55.5%–99.8%), with the lowest risk of recurrence observed in patients receiving gross-total resection with adjuvant proton therapy (23%). CONCLUSIONS Following resection, adjuvant proton therapy was associated with a lower risk of chordoma recurrence compared with photon therapy. The described machine learning models were able to predict tumor progression based on the extent of tumor resection and adjuvant radiotherapy modality used.
Frailty as a Predictor of Postoperative Morbidity and Mortality in Patients Aged 80 Years and Older Undergoing Instrumented Fusion
BACKGROUND AND OBJECTIVES: Degenerative spine disease is a leading cause of disability, with increasing prevalence in the older patients. While age has been identified as an independent predictor of outcomes, its predictive value is limited for similar older patients. Here, we aimed to determine the most predictive frailty score of adverse events in patients aged 80 and older undergoing instrumented lumbar fusion. METHODS: We proceeded with a multisite (3 tertiary academic centers) retrospective review including patients undergoing instrumented fusion aged 80 and older from January 2010 to present. A composite end point encompassing 30-day return to operating room, readmission, and mortality was created. We estimated the area under the receiver operating characteristic curve for frailty scores (Modified Frailty Index-5 [MFI-5], Modified Frailty Index-11 [MFI-11], and Charlson Comorbidity Index [CCI]) in relation to that composite score. In addition, we estimated the association between each score and the composite end point by means of logistic regression. RESULTS: A total of 153 patients with an average age of 85 years at the time of surgery were included. We observed a 30-day readmission rate of 11.1%, reoperation of 3.9%, and mortality of 0.6%. The overall rate of the composite end point at 30 days was 25 (15.1%). The AUC for MFI-5 was 0.597 (0.501-0.693), for MFI-11 was 0.620 (0.518-0.723), and for CCI was 0.564 (0.453-0.675). The association between the scores and composite end point did not reach statistical significance for MFI-5 (odds ratio [OR] = 1.45 [0.98-2.15], P = .061) and CCI (OR = 1.13 [0.97-1.31], P = .113) but was statistically significant for MFI-11 (OR = 1.46 [1.07-2.00], P = .018). CONCLUSION: This is the largest study comparing frailty index scores in octogenarians undergoing instrumented lumbar fusion. Our findings suggest that while MFI-11 score correlated with adverse events, the predictive ability of existing scores remains limited, highlighting the need for better approaches to identify select patients at age extremes.
Surgical management of malignant melanotic nerve sheath tumors: an institutional experience and systematic review of the literature
OBJECTIVE Malignant melanotic nerve sheath tumors are rare tumors characterized by neoplastic melanin-producing Schwann cells. In this study, the authors report their institution’s experience in treating spinal and peripheral malignant melanotic nerve sheath tumors and compare their results with the literature. METHODS Data were collected from 8 patients who underwent surgical treatment for malignant melanotic nerve sheath tumors between 1996 and 2023 at Mayo Clinic and 63 patients from the literature. Time-to-event analyses were performed for the combined group of 71 cases to evaluate the risk of recurrence, metastasis, and death based on tumor location and type of treatment received. Unpaired 2-sample t-tests and Fisher’s exact tests were used to determine statistical significance between groups. RESULTS Between 1996 and 2023, 8 patients with malignant melanotic nerve sheath tumors underwent surgery at the authors’ institution, while 63 patients were identified in the literature. The authors’ patients and those in the literature had the same mean age at diagnosis (43 years). At the authors’ institution, 5 patients (63%) experienced metastasis, 6 patients (75%) experienced long-term recurrence, and 5 patients (62.5%) died. In the literature, most patients (60.3%) were males, with a peak incidence between the 4th and 5th decades of life. Nineteen patients (31.1%) were diagnosed with Carney complex. Nerve root tumors accounted for most presentations (n = 39, 61.9%). Moreover, 24 patients (38.1%) had intradural lesions, with 54.2% (n = 13) being intramedullary and 45.8% (n = 11) extramedullary. Most patients underwent gross-total resection (GTR) (n = 41, 66.1%), followed by subtotal resection (STR) (n = 12, 19.4%), STR with radiation therapy (9.7%), and GTR with radiation therapy (4.8%). Sixteen patients (27.6%) experienced metastasis, 23 (39.7%) experienced recurrence, and 13 (22%) died. Kaplan-Meier analyses showed no significant differences among treatment approaches in terms of recurrence-free, metastasis-free, and overall survival (p > 0.05). Similar results were obtained when looking at the differences with respect to intradural versus nerve root location of the tumor (p > 0.05). CONCLUSIONS Malignant melanotic nerve sheath tumors are rare tumors with a high potential for malignancy. They carry a dismal prognosis, with a pooled local recurrence rate of 42%, distant metastasis rate of 27%, and mortality rate of 26%. The findings from this study suggest a trend favoring the use of GTR alone or STR with radiation therapy over STR alone. Mortality was similar regardless, which highlights the need for the development of effective treatment options to improve survival in patients with melanotic schwannomas.
General Versus Nongeneral Anesthesia for Spinal Surgery: A Comparative National Analysis of Reimbursement Trends Over 10 Years
BACKGROUND AND OBJECTIVES: Nongeneral anesthesia (non-GA) spine surgery is growing in popularity and has facilitated earlier postoperative recovery, reduced cost, and fewer complications compared with spine surgery under general anesthesia (GA). Changes in reimbursement policies have been demonstrated to correlate with clinical practice; however, they have yet to be studied for GA vs non-GA spine procedures. We aimed to investigate trends in physician reimbursement for GA vs non-GA spine surgery in the United States. METHODS: We queried the ACS-NSQIP for GA and non-GA (regional, epidural, spinal, and anesthesia care/intravenous sedation) spine surgeries during 2011–2020. Work relative value units per operative hour (wRVUs/h) were retrieved for decompression or stabilization of the cervical, thoracic, and lumbar spine. Propensity score matching (1:1) was performed using all baseline variables. RESULTS: We included 474 706 patients who underwent spine decompression or stabilization procedures. GA was used in 472 248 operations, whereas 2458 operations were non-GA. The proportion of non-GA spine operations significantly increased during the study period. Operative times ( P < .001) and length of stays ( P < .001) were shorter in non-GA when compared with GA procedures. Non-GA lumbar procedures had significantly higher wRVUs/h when compared with the same procedures performed under GA (decompression; P < .001 and stabilization; P = .039). However, the same could not be said about cervicothoracic procedures. Lumbar decompression surgeries using non-GA witnessed significant yearly increase in wRVUs/h ( P < .01) contrary to GA ( P = .72). Physician reimbursement remained stable for procedures of the cervical or thoracic spine regardless of the anesthesia. CONCLUSION: Non-GA lumbar decompressions and stabilizations are associated with higher and increasing reimbursement trends (wRVUs/h) compared with those under GA. Reimbursement for cervical and thoracic surgeries was equal regardless of the type of anesthesia and being relatively stable during the study period. The adoption of a non-GA technique relative to the GA increased significantly during the study period.
In Reply: Spine Surgery Under Spinal vs General Anesthesia: Prospective Analysis of Quality of Life, Fatigue, and Cognition
Background: Spinal synovial cysts are cystic dilatations of synovial sheaths that extrude into the spinal canal. Despite their generally benign behavior, they can cause severe symptoms due to compression of neural structures. They are most commonly found in the lumbar spine and are rare in the cervical region, especially at the atlanto-occipital junction. Case Description: A 65-year-old presented with neck pain and headaches. The magnetic resonance imaging (MRI) revealed a degenerative cyst within the anterior foramen magnum causing anterior spinal cord and brainstem compression. Multiple surgical treatment options were discussed, and he was prescribed methylprednisolone and immobilization of his cervical spine with a rigid collar. One month later, the patient reported dramatic improvement of his symptoms, and no surgery was performed. One year later, his pain had remained much improved with the continued use of the collar and pain management (i.e., using anti-inflammatories and muscle relaxants). The 1-year follow-up MRI showed the atlanto-occipital cyst compressing the cervicomedullary junction had completely resolved along with the brainstem compression. Conclusion: A 65-year-old presented with myelopathy attributed to a large anterior foramen magnum atlanto-occipital cyst compressing the cord. Conservative management for 1 month with a rigid cervical collar and steroids resulted in marked neurological improvement; at 1 year follow-up, the patient was markedly improved with an MR that demonstrated spontaneous cyst regression.
Semiautomated intraoperative measurement of Cobb angle and coronal C7 plumb line using deep learning and computer vision for scoliosis correction: a feasibility study
OBJECTIVE Scoliosis is a degenerative disease with a 3D deformity in the alignment of the spinal column. Surgical spinal correction outcomes are heavily dependent on the surgeon’s expertise and use of visual cues because of time requirements, lack of automation, and radiation exposure associated with current intraoperative measurement techniques. In this study, the authors sought to validate a novel, nonradiographic, and semiautomated device that measures spinal alignment intraoperatively using deep learning and computer vision. METHODS To obtain spinal alignment metrics intraoperatively, the surgeon placed 3D-printed markers made of acrylonitrile butadiene styrene (ABS) plastic at designated locations in the surgical field. With the high-definition camera of the device, the surgeon can take an image of the markers in the surgical field. Images are processed through a computer vision model that detects the location of the markers and calculates the Cobb angle and coronal plumb line. The marker detection model was trained on 100 images and tested on 130 images of the ABS markers in various conditions. To verify the Cobb angle calculation, 50 models of angle templates from 0° to 180° in 3.6735° increments were created for testing. To verify the plumb line calculation, 21 models of plumb line measurements from −10 to +10 cm in increments of 1 cm were created for testing. A validation study was performed on a scoliotic cadaver model, and the radiographic calculations for Cobb angle and plumb line were compared with the device’s calculations. RESULTS The area under the curve for the marker detection model was 0.979 for Cobb angle white, 0.791 for Cobb angle black, and 1 for the plumb line model. The average absolute difference between expected and measured Cobb angles on the verification models was 1.726° ± 1.259°, within the clinical acceptable error of 5°. The average absolute difference between the expected and measured plumb lines on the verification models was 0.415 ± 0.255 cm. For the cadaver validation study, the differences between the radiographic and device calculations for the Cobb angle and plumb line were 2.78° and 0.29 cm, respectively. CONCLUSIONS The authors developed and validated a nonradiographic, semiautomated device that utilizes deep learning and computer vision to measure spinal metrics intraoperatively.
Spine Surgery Under Spinal vs General Anesthesia: Prospective Analysis of Quality of Life, Fatigue, and Cognition
BACKGROUND: There has recently been increasing interest in the use of spinal anesthesia (SA) for spine surgery. The literature that compared spine surgery under SA vs general anesthesia (GA) focused on safety, perioperative outcomes, and costs. OBJECTIVE: To test if SA is associated with less postoperative fatigue, cognitive dysfunction, and better quality of life in patients undergoing lumbar spine surgery compared with GA. METHODS: We conducted a prospective nonrandomized study in patients undergoing elective lumbar spine surgery under SA or GA by a single surgeon. Fatigue was assessed with the fatigue visual analog scale scale (0-10) and Chalder Fatigue Scale, quality of life with Medical Outcomes Study 12-item Short Form (SF-12), and differences in cognition with Mini-Mental State Examination. Patients were baselined before surgery and assessed again 1 mo after surgery. RESULTS: Fifty patients completed the study, 25 underwent surgery under SA and 25 under GA. The groups were homogeneous for baseline clinical characteristics, with no differences in preoperative fatigue, quality of life, and cognition. At 1 mo after surgery, SA compared with GA had better fatigue scores: fatigue visual analog scale (2.9 ± 1.5 vs 5.9 ± 2.3 [ P < .0001]) and Chalder Fatigue Scale (11.2 ± 3.1 vs 16.9 ± 3.9 [ P < .0001]). One month postoperatively, we observed a significant difference in the SF-12 physical component, with SA having 38.8 ± 8.9 vs 29.4 ± 10.3 ( P = .002). We did not observe significant postoperative differences in the SF-12 mental component or Mini-Mental State Examination. CONCLUSION: Our study demonstrates that SA offers unique patient-centered advantages to GA for elective spine surgery. One month after surgery, patients who received SA had less postoperative fatigue and better quality of life.